2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/227001In this paper we discuss the recent advances in the quantitative comparison of accretion, and the accretion:jet coupling, in accreting black holes in both X-ray binaries (where M ~ 10Msun) and Active Galactic Nuclei (10^5Msun < M < 10^9Msun). These similarities include the radiative efficiency and jet power as a function of accretion rate, which are themselves probably the origin of the `fundamental plane of black hole activity'. A second `fundamental plane' which connects mass, accretion rate and timing properties provides us with a further physical diagnostic. Patterns of radio loudness (i.e. jet production) as a function of luminosity and accretion state are shown to be similar for X-ray binaries and AGN. Finally we discuss how neutron stars are a useful control sample, and what the future may hold for this field.Invited Review at the VI Microquasar Workshop: Microquasars and beyond, Sept 18-22 2006, Como, Italy. To be published online by PoSAstrophysicstext